forked from bevyengine/bevy
-
Notifications
You must be signed in to change notification settings - Fork 0
/
globals.rs
67 lines (60 loc) · 2.03 KB
/
globals.rs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
use crate::{
extract_resource::ExtractResource,
render_resource::{ShaderType, UniformBuffer},
renderer::{RenderDevice, RenderQueue},
Extract, RenderApp, RenderStage,
};
use bevy_app::{App, Plugin};
use bevy_core::FrameCount;
use bevy_ecs::prelude::*;
use bevy_reflect::Reflect;
use bevy_time::Time;
pub struct GlobalsPlugin;
impl Plugin for GlobalsPlugin {
fn build(&self, app: &mut App) {
if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {
render_app
.init_resource::<GlobalsBuffer>()
.init_resource::<Time>()
.add_system_to_stage(RenderStage::Extract, extract_time)
.add_system_to_stage(RenderStage::Prepare, prepare_globals_buffer);
}
}
}
fn extract_time(mut commands: Commands, time: Extract<Res<Time>>) {
commands.insert_resource(time.clone());
}
/// Contains global values useful when writing shaders.
/// Currently only contains values related to time.
#[derive(Default, Clone, Resource, ExtractResource, Reflect, ShaderType)]
#[reflect(Resource)]
pub struct GlobalsUniform {
/// The time since startup in seconds.
/// Wraps to 0 after 1 hour.
time: f32,
/// The delta time since the previous frame in seconds
delta_time: f32,
/// Frame count since the start of the app.
/// It wraps to zero when it reaches the maximum value of a u32.
frame_count: u32,
}
/// The buffer containing the [`GlobalsUniform`]
#[derive(Resource, Default)]
pub struct GlobalsBuffer {
pub buffer: UniformBuffer<GlobalsUniform>,
}
fn prepare_globals_buffer(
render_device: Res<RenderDevice>,
render_queue: Res<RenderQueue>,
mut globals_buffer: ResMut<GlobalsBuffer>,
time: Res<Time>,
frame_count: Res<FrameCount>,
) {
let buffer = globals_buffer.buffer.get_mut();
buffer.time = time.seconds_since_startup_wrapped_f32();
buffer.delta_time = time.delta_seconds();
buffer.frame_count = frame_count.0;
globals_buffer
.buffer
.write_buffer(&render_device, &render_queue);
}